(1) Field of the Invention
The present invention relates to a one-step route to 5-trityloxymethyl-oxazolidinone from 3-hydroxy-4-trityloxy butyramide. In particular, the present invention relates to the preparation of chiral forms of the 5-trityloxymethyl-2-oxazolidinone.
(2) Description of Related Art
Optically pure oxazolidinones can be obtained by carbonylation of vicinal amino alcohols with reagents such as phosgene, ethyl chloroformate and carbonyl imidazole. The preparation of optically-pure 5-trityloxymethyl-oxazolidinone would normally require the preparation of the corresponding optically-pure 5-hydroxymethyl-oxazolidinone followed by a tritylation step to produce 5-trityloxymethyl oxazolidinone.
Oxazolidinones have emerged as a very important class of compounds in drug development especially in the areas of antimicrobials (Diekema, D. J., et al., Drugs 59 7-16 (2000)) and behavioral disorders (Brenner, R., et al., Clin. Therapeut. 22 4 411-419 (2000)). They are especially active against some of the most resistant human pathogens including vancomycin-resistant enterococci, methicillin-resistant Staphylococcus aureus, cephalosporin-resistant Streptococcus pneumoniae and several organisms that display penicillin resistance (Diekema, D. J., et al., Drugs 59 7-16 (2000)). Linezolid (4) was recently recommended for approval for the treatment of infections from antibiotic resistant bacterial strains especially those that are resistant to vancomycin. ##STR1##
Optically active 3,4-dihydroxybutanoic acids and their .gamma.-lactones are important sources of chirality. They can be obtained in commercial quantities from carbohydrates such as starch, lactose, maltodextrins, cellulose and arabinose by oxidative degradation (Hollingsworth, R. I. Biotechnology Annual Review 2 281-291 (1996); Hollingsworth, R. I., J. Org. Chem. 64 7633-7634 (1999)). See also U.S. Pat. Nos. 5,292,939, 5,808,107, 5,319,110 and 5,374,773 to Hollingsworth. Chiral amino propane diols can be made by Hoffman degradation of the isopropylidene acetals of optically active 3,4-dihydroxybutyric acid amides (Wang, G., et al., J. Org. Chem. 64 1036-1038 (1999)).